采用磁流变阻尼器的斜拉索半主动控制

采用基于位移和速度方向的半主动控制算法，对斜拉索和磁流变阻尼器组成的系统进行了动力分析．考察了斜拉索基频（张力、索长、质量）、Irvine参数、激励荷载（类型、频率、大小）等各种因素对斜拉索动力响应的影响，并与磁流变阻尼器被动控制、最优粘性油阻尼器控制效果进行了比较．以全索全时段振动响应的均方根作为振动控制效果的评价指标．研究表明：磁流变阻尼器半主动控制对斜拉索抑振效果比磁流变阻尼器被动控制、最优粘性油阻尼器有较大幅度的提高；索全长全时程振动响应的位移均方根减小幅度可达50％，且在磁流变阻尼器型号的有效区间内，可使多阶振动模态均取得较好的减振效果．

MR Dampers-Based Semi-Active Control Strategy of Cable-Stayed Vibration

A semi-active control strategies of cable vibration with MR dampers is presented on the basis of the direction of both displacement and velocity.A theoretical model for the cable damper system is formulated by accounting for the cable inclination and sag effect based on the Himilton's principle.Spencer model is used for MR dampers.The primary measure of damper performance is the Root Mean Square(RMS) cable deflection integrated along the length of the cable during the whole time.The relationship of the optimal marker of MR dampers,mounting postion,voltage applied,the first frequency of cables(tensile force,length and mass perunit length) and excited loads(type,frequency and amount) is studied.A comparative study is made among the semi-active MR Dampers strategy,the optimal passive MR damper and the optimal oil damper.Results show that the proposed semi-active dynamic is of a better control performance when MR dampers marker is within the effective region.The strategy is robust and quite easy to be applied when fewer sensors is needed.The dynamic range of MR dampers are sufficiently wide.The RMS of displacement is reduced by more than 50%.